Low-emittance emission of energetic multiple charged ions from short-pulse-laser produced plasmas

Emission of multi-MeV multiple-charged ions from a target irradiated by a short laser pulse in the range of intensity 10¹⁶⁻²⁰W/cm² is investigated via a full kinetic particle-in-cell simulations including transient plasma ionization. The anisotropy of the velocity distribution of hot electrons, which dominate the ion acceleration, is found to enhance the ion energy and improve the emittance. Ions over MeV energy are accelerated from non-low-Z matter with up to a 10% conversion from laser energy. A high current, 1 ps duration, short-laser-pulse driven contact ion source based on the modification of the target surface via the laser-induced spallation is discussed.